arm64: dts: ti: k3-am642-evm-icssg1-dualemac: add overlay for mii mode

Add device tree overlay to enable both ICSSG1 ports available on AM64x-EVM
in MII mode.

Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
Reviewed-by: Ravi Gunasekaran <r-gunasekaran@ti.com>
Link: https://lore.kernel.org/r/20240429092919.657629-1-danishanwar@ti.com


Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>